Objective:To investigate the relations between the shape of corneal topography and visual acuity at different stages after excimer laser in situ keratomileusis.Methods:139 cases (255 eyes) of myopia were operated with excimer laser in situ keratomileusis.They were classified into 2 groups: low,middle group (Ⅰgroup:-1 25~-6 00D,125 eyes) and high group (Ⅱgroup:-6 25~-20 50D,130 eyes) according to the refractive diopters.The visual acuity and corneal topography were examined before operation and at the third and sixth month postoperative follow-up visits. Results:Compare the results at 6 month with those at 3 month, there are significant differences in the Simulated keratoscope (SimK) reading.The refractive diopters do not change evidently in Ⅰgroup but change in Ⅱgroup.The shape of the topography decides the visual acuity.Conclusion: The Simulated keratoscope (SimK) reading and the shape of corneal topography are closely related to postoperative results.